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1.
京西稻是清康熙、雍正、乾隆等亲自选育的优良品种,在与紫禁城并重的“三山五园”政治中心内外种植,具有多重价值属性,属于皇家御稻。从2000年起,基于北京水资源匮乏等原因,京西稻种植面积大幅度降至134 hm2左右,处于濒危状态。在保护传承过程中,京西稻入选中国重要农业文化遗产目录。在新修订的《北京历史文化名城保护条例》中,又将京西稻列入遗产保护目录。在海淀区,京西稻已经深入公园、学校、社区、酒店等地,在教育文化中发挥着农业以外的作用。 相似文献
2.
为明确垦稻26和龙粳31高产优质栽培的株行距和穴苗数处理,采取裂区设计进行试验研究。结果表明,最优群体因品种而异,垦稻26在株距10cm、行距30cm、5苗/穴产量最佳,龙粳31则以株距13.3cm、行距27cm、9苗/穴产量最佳;垦稻26在5苗/穴、行株距30cm×10cm处理,有利于提高稻米的碾磨品质,不利于改善稻米的外观品质,营养品质较低,利于改善稻米的食味品质,且食味评分值高达86.5,显著高于最低处理;龙粳31在5苗/穴、行株距27cm×13.3cm处理,碾磨品质较高,不利于营养品质和外观品质的改善,食味品质得到明显改善,食味评分值高达86.0,与最低处理差异达显著水平。因此,高产优质栽培要因品种选择适宜的穴苗数和株行距,是实现水稻高产优质最为快捷、最为经济有效的措施。 相似文献
3.
Bertrand C. Y. Collard Joseph C. Beredo Bert Lenaerts Rhulyx Mendoza Ronald Santelices Vitaliano Lopena 《Plant Production Science》2017,20(4):337-352
Rice production needs to increase in the future in order to meet increasing demands. The development of new improved and higher yielding varieties more quickly will be needed to meet this demand. However, most rice breeding programmes in the world have not changed in several decades. In this article, we revisit the evidence in favour of using rapid generation advance (RGA) as a routine breeding method. We describe preliminary activities at the International Rice Research Institute (IRRI) to re-establish RGA on a large scale as the main breeding method for irrigated rice breeding. We also describe experiences from the early adoption at the Bangladesh Rice Research Institute. Evaluation of RGA breeding lines at IRRI for yield, flowering time and plant height indicated transgressive segregation for all traits. Some RGA lines were also higher yielding than the check varieties. The cost advantages of using RGA compared to the pedigree method were also empirically determined by performing an economic analysis. This indicated that RGA is several times more cost effective and advantages will be realized after 1 year even if facilities need to be built. Based on our experience, and previous independent research empirically testing the RGA method in rice, we recommend that this method should be implemented for routine rice breeding in order to improve breeding efficiency. 相似文献
4.
This study aimed to explore the feasibility of zein as a gluten alternative in preparing sheeted doughs with rice flours containing different amylose contents (12, 19, and 26%) that were successfully slit into noodle strands. Rice-zein mixtures with lower amylose contents exhibited lower pasting parameters and the high amylose paste samples possessed more elastic properties. Higher water absorption was observed in the low amylose rice-zein mixture whereas the use of zein were effective in increasing the stability of rice dough regardless of amylose content. In case of thermal conductivity, the noodle doughs prepared with high amylose rice-zein mixture had low thermal conductivity, probably implying a long cooking time. The structure of the rice-zein noodles had a tendency to become firmer with increasing levels of amylose by showing greater breaking stress and resistance to extension that could be correlated to reduced cooking loss. 相似文献
5.
为了明确水稻条纹病毒(RSV)在水稻和玉米上发生程度差异明显的原因,从一个侧面了解RSV流行本质,2004年在洪泽进行田间试验。采用黄盘诱集、盘扑、盘刮、肉眼计数等方法比较武育粳3号和掖单13上灰飞虱侵入和消长动态,结果表明两者均只有一个成虫侵入高峰,单位面积迁入虫量前者是后者的3.6倍,单株平均虫量相近。Dot-ELISA法测定灰飞虱带毒率为40%,成虫迁移扩散高峰期22d内两者接毒量约为每天百株137头带毒虫。武育粳3号有二代若虫发生,掖单13则无。逐日调查发病进程,结果显示水稻发病率为60%,玉米为0。室内抗性鉴定,掖单13对RSV的抗性比武育粳3号高4个级别。综合以上结果,寄主品种抗性决定了RSV在水稻和玉米上流行状况,二代若虫重复侵染是RSV在水稻上重发的另一主要原因。 相似文献
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在空中核爆炸的情况下,光辐射是损毁水稻的主要因素,光辐射可使三叶期、分蘖期水稻的叶片烧损、株高降低,其损毁程度随着距爆心距离的加大而减弱,叶片受到烧损仍然存活的植株,爆后可迅速恢复生长,叶片数、株高在较短时间内即可达对照水平,分蘖能力也不受影响。收获时大部分受损水稻的穗长、穗粒数、千粒重、平均单株分蘖数、 相似文献
10.
P. Banik 《Journal of Agronomy and Crop Science》1996,176(5):289-294
A field experiment was conducted during the winter season of 1992–93 and 1993–94 at Agricultural Experimental Farm, Giridih, Bihar to evaluate the intercropping systems of legumes, gram ( Cicer arietinum L.), pea ( Pisum sativum ) and lentil ( Lens culinaris ) with wheat ( Triticum aestivum ) in 1:1 and 2:1 'row replacement series'. Intercropping systems were assessed on the basis of new indices termed as actual yield loss (AYL) and intercropping advantage (IA). This paper highlights the comparative effectiveness of evaluating the intercropping systems through the existing intercropping indices like LER, RCC, aggressivity. The indices AYL and IA seem to be more appropriate particularly when per plant yield is considered. Intercropping reduced the yield of component crops compared with respective pure stands. Wheat + pea in 1:1 row replacement series gave the highest wheat yield equivalent value (3.02 t ha−1 ) followed by wheat + lentil (2.91 tha−1 ). When the actual sown proportion was considered wheat + lentil (1:1) resulted in maximum AYL (+0.610) and IA (+0.279) values. This treatment also gave the maximum monetary advantage (Rs 5985.45 ha−1 ). 相似文献